Moneywort comes from Europe and southwestern Asia and was introduced as an ornamental. Though originally contained to just the east coast of the United States, it has spread all over the continental U.S. and up into Canada.
A trailing, mat-forming, perennial with creeping stems that can grow up to 2 feet long and up to four inches high. The leaves are opposite and nearly rounded, resembling small coins, giving the plant its name.
The yellow flowers bloom from June to August, but in some years not at all. Flowers measure approximately one inch in width and may contain small red dots on the petals. Moneywort grows in full sun to full shade, usually in muddy soils along rivers, wet meadows, swamps, stream banks, and disturbed floodplains.
This plant often escapes from cultivation and forms dense mats. It can spread by fragmentation that occurs when an animal breaks off an area or by a piece floating downstream. It also spreads by seed dispersal and the seeds can be carried down streams or by animals.
In the right growing conditions, the plant can thrive and form very dense mats that choke out native vegetation. It grows best in water filled soils like flood plains and along the sides of river banks. Due to its affinity for wet areas, it poses a threat to Concord's wetlands.
Hand pulling is recommended for small plants such as this. This may be easiest in the early spring due to the fact it appears before many native species. Encouraging native grasses and other native species might also prove effective by decreasing the amount of light available to the invasive. Take care not spread any plants that have gone to seed. Remove completely from the site and dispose of in garbage bags or at the town composting site. Foliar spray is not recommended as it can be harmful to the surrounding floura and fauna. See the invasive removal page for how to carry out these methods. Any removal within 100 feet of wetland resource areas, including certified vernal pools, or within 200 feet of a perennial stream may require approval from the Concord Natural Resources Commission. Please contact the Division of Natural Resources before you begin.
The following native plants can serve as a good replacement for garlic mustard in a garden: